<template>
 <div class="todo-footer" v-show="total">
<label>
<!-- <input type="checkbox" :checked="isAll" @change="checkAll"/> -->
<input type="checkbox" v-model="isAll"/>

</label>
<span>
<span >已完成{{ doneTotal}}</span> / {{total}}
</span>
<button class="btn btn-danger" @click="clearAllDone">清除已完成任务</button>
</div>
</template>

<script>
    export default {
        name:'MyFooter',
        props:['todos','checkAllTodo','clearDoneTodo'],
        computed:{
            isAll:{
                get(){
                    return this.doneTotal === this.total && this.total>0;
                },
                set(value){
                    this.checkAllTodo(value)
                }
            },
            total(){
                return this.todos.length
            },
            doneTotal(){
                return this.todos.reduce((pre,todo)=> pre+(todo.done? 1:0), 0)
            }
        },
        methods:{
            clearAllDone(){
                this.clearDoneTodo()
            }
        }
    }
</script>

<style scoped>
todo-footer {
    height: 40px;line-height: 40px;padding-left: 6px;margin-top: 5px;
}

todo-footer label {display:inline-block;margin-right: 20px;cursor: pointer;}

.todo-footer label input {position: relative;top: -1px;vertical-align: middle;margin-right: 5px;}

todo-footer button {float: right;margin-top: 5px;}
</style>